Why Friction Still Matters in UX Design - The Hidden Constraint
Mark Sage - 12 min read - 21/07/2025
When I started out in the world of work, software design looked very different.
Screens and reports were planned on paper — I fondly remember marking an “X” for every character in every field on a 198 character graph paper. We weren’t just solving business problems – we were solving for space. Disk was scarce, memory was limited, and every decision carried a cost.
I began my career in 1991 writing RPG on the IBM System/36. My terminal had a small green screen — now a feature called ‘Dark Mode’ on iOS — but back then it was the only mode you had. My keyboard gave a reassuring click on every press, something I had to physically unscrew to turn it off. In RPG, the development approach was lean, giving you just 99 fixed indicators — Boolean flags of true or false – to hold state and manage program logic. This forced you to think really carefully about how to structure even a basic solution.
Storage wasn’t abstract. We moved software and data using 8-inch floppy disks – 1.2MB each – slotted into 10-disk magazines. A client I worked with, who’d run an earlier system called the IBM System/34, once told me they could tell how full the drives were just by the difference in sound they made.
That world didn’t just teach me how to solve problems. It taught minimisation – the discipline of working within limits. The constraint wasn’t a burden. It was the method.
Back then, the real challenge wasn’t just what to build, but how to fit it into 198 characters of width and a few megabytes of disk. That underlying design challenge is something I describe as the problem of the problem.
Fast forward to 2019, and everything had changed
Cloud computing made resources feel limitless. Interfaces were designed in Figma, not drawn by hand. Middleware patched gaps in functionality, with software more assembled than engineered.
But abundance brought a new kind of constraint. That of simplicity.
When anything is possible, the hard part is knowing what not to build. When features are cheap, clarity becomes expensive.
And so, the problem of the problem didn’t disappear – it just shifted.
This time, the constraint wasn’t technical. It was human.
The hardest part of launching a loyalty programme like yuu Rewards was no longer writing the logic or integrating the data — it was earning attention. We now had to justify our place on a user’s home screen – just like we once had to justify every byte of disk.
We may no longer have needed to fit everything into 198 characters, but we still had to fit into someone’s everyday life.
Back when I was at Aimia, just a few years earlier, we were working on the Nectar app in the UK to see how it could enhance the coalition programme. It was an attempt to add another way to connect, another way to engage. But the challenge we had was that the Nectar app wasn’t solving a problem the consumer actually had.
As a legacy scheme, Nectar had always communicated via printed statements and identified members through plastic cards. From the customer’s perspective, the programme already worked. They could earn and redeem in-store, get updates via email or post, and check balances via the web, till receipt, or even the call centre. There was no real constraint — and without constraint, there was no compelling reason to install an app.
Penetration reflected that. We struggled to move beyond 25%.
But with yuu Rewards, it was entirely different.
There were no plastic cards. No paper statements. No transactional website. The app wasn’t just a channel in the program – it was the programme. And that created a very real constraint. If you didn’t engage with the app, you didn’t engage with the programme at all.
In a coalition model — where multiple brands coexist — that interface becomes even more critical. It’s the shared space between all partners. It’s the one place the member returns to. And yet, it’s often overlooked.
Too often, when building a loyalty programme, the app is treated as a side show. Something to get to later — if at all — after data, rewards, comms, and partners are sorted. But none of that matters if the member doesn’t engage.
And engagement starts with the interface.
Sure, our primary problem for yuu Rewards was launching a multi-partner loyalty programme. But the deeper problem — the problem of the problem — was how to do it in a way that would actually connect with users.
This is because the battleground for loyalty isn’t just who has the best rewards or biggest partners. It’s also who has the simplest, most elegant, most intuitive app.
That’s where the edge is. That’s what we had to solve for.
Being digital first was our primary aim — which is to say we wanted interactions with the programme to be first and foremost, via digital channels. But not just any digital channels, we specifically wanted to be mobile first, leveraging native apps across iOS and Android, as well as a mini-programme within WeChat.
In todays digital world, the real competition is consumer attention — and the currency is relevance.
To be relevant, you need to be present. Getting installed on a user’s phone was the first battle.
However, before diving into the core UX and UI design, we established four core design principles to anchor every decision:
Design Principle #1: Frictionless — Every key customer mission — from earning to redeeming to checking points — should be seamless. If it takes effort, we’ve failed. Great design removes steps, reduces clicks, and clears the path.
Design Principle #2: Rewarding — Value must always be front and centre. Members should feel the benefit in every interaction — not buried in fine print or locked behind complexity. The programme exists to reward, and the design should reflect that.
Design Principle #3: Accessible — The programme should feel easy to join and effortless to use. Every participating brand must be clearly visible, and the ways to collect must be obvious. Visibility drives confidence and participation.
Design Principle #4: Engaging — Loyalty should be fun. From gamified challenges to celebratory animations, we’re designing it to spark joy and encourage repeat interaction. Emotional engagement drives behavioural loyalty.
You could argue that all apps would want these design principles. Who doesn’t want to be ‘frictionless’ and ‘engaging’. But when you’re building something complex, it’s easy to solve for functionality and lose sight of the user. These principles kept us grounded in solving the right problems.
They also helped us navigate key design tensions across three core user missions:.
1. Payment — Members needed immediate access to their QR code at checkout. Any delay risked losing the basket and the customer.
2. Browse — When opening the app outside of a store, we wanted members to be inspired and encouraged to make a visit. This is where we grow customer value.
3. Shop — When inside a store, members wanted brand-specific content. We had to reduce noise and surface relevant value.
The challenge here was how to quickly allow filtering to a given brand, whilst not losing visibility and inspiration for all brands. Keeping the QR code accessible while still encouraging content browsing. Showing people their progress, whilst still encouraging them to do more.
There was no single answer — but our design principles helped us weigh the trade-offs.
Take the offer feed as an example. It could’ve been purely functional — dense with deals, overloaded with filters, designed for utility. Instead, we built it with all four principles in mind.
We took inspiration from Instagram. A vertically scrolling, image-led feed that encouraged lazy browsing. It was frictionless, familiar, and visually rewarding. Offers peeked from below the fold, inviting ongoing discovery. New offers appeared daily, with older ones aging and falling down the feed — making each app open feel fresh and rewarding.
Visual cues like stickers added clear calls to action. Each tile showed its brand so users could instantly find the familiar but also discover something new. Importantly, each tile had a templated style, both in terms of layout and design — this helped ensure a more visually aligned content which was image rich. These design features helped make it accessible and engaging.
At the top of the feed, we showed banner logos — not static, but ranked according to personalised relevance. This gave users quick access to favourite brands without needing to leave the feed. No clunky filter screens. No breaking the scroll. Just smooth, dynamic interaction.
This is how the design principles showed up in practice. They weren’t slogans — they were our product guardrails. In moments of complexity or competing priorities, we came back to them. They helped us avoid the trap of overdesign and feature bloat.
They reminded us that our job wasn’t just to solve the problem- it was to solve the problem of the problem.
There was though a fifth design principle — one we rarely talked about publicly.
Design Principle #5: Mutuality — All access to loyalty is through loyalty. We preserve shared visibility and collective value. Ensuring brand share of market doesn’t distort brand share of voice.
In a coalition, the app interface is shared real estate. Letting one brand redirect engagement away from that space risks reducing exposure for everyone else. Mutuality was our way of making sure every partner benefited from the whole, not just their part.
This meant no QR codes in partner apps. No redemption outside the yuu ecosystem. Even partner-led enrolment, such as through e-commerce, had to use our branded templates and stay under our control.
Why? Because we were jealously guarding the ecosystem — not out of stubbornness, but out of strategic necessity.
If a dominant brand enabled earn or burn in their own app, they’d naturally absorb more user attention. That would reduce loyalty app opens, lower visibility for smaller brands, and weakens the coalition effect. And it’s the smaller brands who’d suffer most.
As Byron Sharp’s law of double jeopardy reminds us, smaller brands already suffer from both fewer buyers and less loyal buyers. A coalition model can smooth that out — lifting all boats; however, dilute the shared interface and that lift starts to disappear.
From the outside, it may have seemed petty, but in reality, it was principled. Centralising access wasn’t about control, it was about protecting the ecosystem value for everyone — including the member.
Maintaining this principle wasn’t easy though. We faced pressure early on from some of the brands, and it didn’t stop post-launch. But it’s even harder to hold the line if you don’t have a principle to stand behind.
Mutuality was ours.
The clear design principles helped us move quickly. Working with Deloitte Digital as our build partner, we completed our first UX study by 18th June 2019 — just one month after kicking off the build!
The study was structured as a two-day workshop to understand what users needed from a loyalty app. We interviewed participants with experience across local programmes like MoneyBack, Asia Miles, and our own Manncard scheme at Mannings. The goal was to identify the key jobs to be done — the tasks users were trying to accomplish — and understand how they described those tasks in their own words. For example, what phrase would they expect to tap if they wanted to check their account history?
We then ran a card sorting exercise, a classic UX method for exploring how users mentally group information. Participants were asked to organise features and functions into intuitive categories. This gave us a better understanding of:-
1. How users interpreted our labels
2. How they expected features to be grouped
3. What is the route to get there, including the primary tasks — likely to belong on the home screen.
The exercise also revealed how critical language is to interface design — a major factor in delivering a Frictionless and Accessible experience. If users can’t find what they’re looking for, or misunderstand what a label means, the result is frustration and disengagement.
For example, we tested the label “My Offers”. While it seemed innocuous, many users interpreted it as personalised offers — tailored to their preferences or behaviours. That was fine if true. But if the section was actually displaying general promotions, the label created a mismatch between expectation and experience. It was a small semantic difference — but with big consequences for usability.
Having done our first user research, we were on a role. The next step was designing and testing our wireframes.
Now just August 2019, we developed two early designs — Design A and Design B — to test different philosophies. Design A followed a functional, promotion-led layout. Design B took inspiration from social media — visually rich, scrollable, and simplified.
The general business demand was for more — for Design A — as this would allow more content, more offers and more ad space. But we were focused on the problem of the problem — that of consumer engagement — and so felt that for this, less is more.
To help decide, we ran a preference test with internal users. Rather than asking for detailed feedback, we focused on emotional impressions.
Participants rated the designs across five dimensions — “Easier”, “Relevant”, “Pleasant”, “Attractive”, and “Closer” — by choosing one design for each. This forced trade-offs and highlighted the dominant preference.
Design B emerged as the clear winner. There was no perfect design. No single layout could satisfy every user or use case. But Design B worked for most.
What stood out for me wasn’t just the score, but the sentiment. One participant summarised it perfectly:
“Design A is functionally driven, but Design B feels social and emotional.”
Interestingly, at this point there were no social features in the design. But by borrowing visual language from social media — large images, smooth scrolling, continuous feed — we tapped into a familiar design equity. The same content, the same functions, but positioned in a more lifestyle-driven, emotionally engaging way.
Design B won and just a year later it was in the hands of over 2m people.
Several further rounds of user testing were conducted as we moved from wireframes to working prototypes. However, our initial sessions didn’t focus on our app at all, and instead focused on our competitors.
We invited consumers to complete scripted jobs to be done using market-leading loyalty apps. Tasks included simple actions like “check your balance” or “redeem a reward.” We observed how users navigated each app, recorded their responses, and captured their emotional reactions along the way.
This testing had two goals. First, to identify where competitor apps fell short and what problems we could solve better.
Second, to create a benchmark. Our primary target was MoneyBack — Hong Kong’s most established coalition app at the time — so we wanted a baseline to compare against when our app was ready.
In September 2019, we gathered our first batch of insights.
We learned what users valued most — easy access to the QR code and to offers. We saw what they didn’t care for — things like inboxes and point-sharing. They wanted more visuals, fewer words. They disliked repetitive content and overtly ad-like placements. Pain points included being pushed out of the app to a browser, and friction came from multi-step redemption flows.
All of this fed into our design.
By early 2020, we were ready to go head-to-head with MoneyBack.
Their app had over 3 million users and had been in the market for years. It powered a similar coalition model, centred around grocery. In many ways, it was the incumbent we were setting out to disrupt.
Our test plan was simple. Users would complete the same core tasks in both apps — then score the experiences across two dimensions: ease of use and emotional response.
Then COVID hit.
In-person testing was no longer an option. This was March 2020 and a moment of uncertainty and fear. No one wanted to sit in a room with strangers.
So we took the whole process remote.
We recruited testers via Facebook ads and ran video calls using screen-sharing tools. We could still observe their behaviour and reactions in real time — just from a safe, social distance.
The results of this face-off started… well flat. Our onboarding and login flows were rated by users as “ordinary,” with no meaningful edge over the competitor.
But when users landed on our homepage, everything changed.
We were rated 2x more appealing and 2x more informative than MoneyBack. Our visually-led offer tiles scored 4x higher, and 90% of users rated the offer details as “accessible.”
Core journeys like saving and redeeming were rated 2x more intuitive. Even our QR code page — a functional necessity — was described as more “exciting.”
Overall, 70% of respondents gave us highly positive emotional ratings like Delighted, Playful, and Creative. Only 30% found us “Common” or “Ordinary” — compared to 50% for MoneyBack.
From this user testing, we were confident we had built something compelling, delightful and emotionally relevant. The data told us. Our users told us.
But data only gets your so far.
A lot has changed since the days when a seasoned engineer could gauge disk utilisation by the sound of an IBM System/34. But one thing hasn’t — human intuition still matters. It still takes experience — not just research — to bridge technology, creativity, and user design.
So, with that in mind — and despite Design Principle #1 — we added a little friction back in.
Because sometimes, the best way to move forward… is to slow the user down.